Here in New York City, activists declared Friday a “Climate Emergency Day” as they observed the famous Climate Clock in Union Square ticking down from seven years to six years. The clock marks the estimated time left to keep global heating below 1.5 degrees Celsius.

Speaking with ABC’s “This Week,” former Vice President Al Gore said on Sunday that extreme weather events will get even worse without immediate action on climate.

Al Gore: “If we don’t stop using our atmosphere as an open sewer and if we don’t stop these heat-trapping emissions, things are going to get a lot worse. More people will be killed, and the survival of our civilization is at stake.”